Nut and tail assembly and method for the production thereof said tail including a rigid outer sleeve

ABSTRACT

A nut and tail assembly ( 10 ) and method of manufacture including a nut ( 12 ) having a first end and an inward flange ( 24 ) at the other end, a longitudinal cylindrical hollow body ( 14 ) having a first end and a second end at which is located an outstanding flange ( 40 ) and a circular longitudinal sleeve ( 16 ). The sleeve ( 16 ) extends along said sliding surface and has a flange ( 44 ) at a first end abutting against the body flange ( 24 ). A stop ( 34 ) is located between the ends of the body ( 14 ) and defines a cavity sliding surface generally parallel to the longitudinal body between the stop ( 34 ) and flange ( 44 ). The nut inward flange ( 24 ) extends into the body cavity and is of a large enough diameter to be able to slide on said body sliding surface but small enough to be held within said cavity defined between said stop ( 34 ) and sleeve flange ( 44 ). Projections ( 50 ) on the sleeve flange ( 44 ) assist in locating the sleeve ( 16 ) relative to the nut ( 12 ) during the moulding process.

[0001] The present invention relates to a pipe or conduit assembly orfitting including an outer member rotatable over an inner member saidinner member including a rigid outer sleeve extending over a part ofsaid tail assembly, and to a method of production thereof including anydies for the production of such a fitting.

BACKGROUND OF THE INVENTION

[0002] Nut and tail assemblies are typically moulded from plasticsmaterial, the typical assembly including a tail having an externalthread at one end and an outstanding flange or lip at the other end witha stem extending therein between, said assembly also including a nuthaving an inturned flange that bears against the back of the tailoutstanding flange and is arranged to firmly retain the assembly to amale threaded fitting. These fittings can be made many ways such asspin-welding or two-part operations. Other conduit fittings such asbarrel unions, and fittings on the ends of valves can be made by thesame methods.

[0003] In a previous patent by the same applicant, Australian Patent579,134, whose contents are expressly incorporated by reference herein,there was disclosed both a method and a fitting manufactured by saidmethod that greatly simplified the construction of such a fitting havinga nut and tail of moulded plastics material. The method included placingthe nut in a die and moulding the tail with the nut in one single dieoperation so that the tail outstanding flange was moulded within thebody of the nut, the nut inturned flange located behind the outstandingflange of the tail. Such a method and fitting greatly simplified thethen known manufacturing processes.

[0004] Although the fitting as described in the aforementioned patenthas been found to work satisfactory in most circumstances it has beenfound that lateral twisting and bending of such a fitting can causefailure in the fitting especially in the body of the tail or stemimmediately adjacent the inturned flange of the nut. In situations wheresuch a fitting may be prone to lateral forces this type of fitting istherefore unsuitable.

[0005] It is an object of the present invention to propose improvementsin such a fitting and construction thereof whereby there is proposed afitting having a nut, a tail of moulded plastics material, a sleeveextending at least partially over said tail and formed of a resilientmaterial.

[0006] It is a further object of the preset invention to provide forimprovements in the construction of such a fitting or at least providethe public with a useful alternative.

SUMMARY OF THE INVENTION

[0007] Therefore in one form of the invention there is proposed a nutand tail assembly including:

[0008] a longitudinal cylindrical hollow body having a first end, saidbody including an outwardly extending stop located inwardly from saidfirst end, said body further having an outstanding flange at the secondend thereof, said stop and flange defining therein between a cavitysliding surface generally parallel to the longitudinal body;

[0009] a circular longitudinal sleeve extending along said slidingsurface;

[0010] a nut having a first end, and an inward flange at the other end,said nut inward flange extending into said body cavity and being of adiameter to be able to slide on said body sliding surface.

[0011] In a further form of the invention there is proposed a nut andtail assembly including:

[0012] a longitudinal cylindrical hollow body having a first end, saidbody including an outwardly extending stop located inwardly from saidfirst end, said body further having an outstanding flange at the secondend thereof, said stop and flange defining therein between a cavitysliding surface generally parallel to the longitudinal body;

[0013] a circular longitudinal sleeve extending along said slidingsurface and having a flange at a first end thereof, said flange abuttingagainst said body flange;

[0014] a nut having a first end, and an inward flange at the other end,said nut inward flange extending into said body cavity and being of adiameter to be able to slide on said body sliding surface.

[0015] In preference said body first end includes a plurality ofexternal threads. Of course other types of connections including snap-ontype fitting could well be employed.

[0016] Preferably said nut includes a plurality of internal threads atsaid first end.

[0017] In preference said sleeve other end extends into said body. It istherefore anchored into the body and is integral with the body.

[0018] In preference said sleeve other end includes at least one groovewherein said groove assist in longitudinally anchoring said sleeve insaid body.

[0019] In preference said body is manufactured from polymeric plastic.This enables it to be moulded in a die operation.

[0020] In preference said sleeve is manufactured from metal. This mayinclude various metals such as brass that then give the fitting strengthagainst bending and twisting.

[0021] In preference said sleeve includes projections extendinglongitudinally outwardly from said flange. These projections helplocated the sleeve before moulding.

[0022] In preference said projections are located symmetrically andcircumferentially on said flange.

[0023] In preference there are at least four said projections. Theseprojections may be small pin-like projections although they may equallywell be blocks.

[0024] Preferably located in between said sleeve and said externalthreads is a torque converter to assist in controlling the rotationalmotion of the body including said tail and sleeve.

[0025] In preference the assembly includes a gasket housed within saidnut and abutting against said body outstanding flange.

[0026] In a yet further form of the invention there is proposed a methodof manufacture of a fitting with an inner member having a sleeve and anouter member that is rotatable over said sleeve, the method includingthe steps of:

[0027] (a) making the outer member to a shape that includes a radiallyinturned annular flange at one end and an axially extending portionhaving an internal thread,

[0028] (b) placing a sleeve within said outer member, said sleeve havinga radial outwardly extending annular flange, said sleeve flange abuttingagainst said outer member flange and extending longitudinally away fromsaid internal thread,

[0029] (c) positioning the outer member and sleeve onto an axiallyaligned male portion of a moulding die and within two female portionssaid male portion including a plurality of locating pins engaging saidsleeve,

[0030] (d) closing the moulding die thereby placing the outer member andsleeve in their final position and establishing a moulding cavity withinwhich is located the outer member and sleeve, part of the surface ofsaid cavity defined by the outer surface of the sleeve annular flange,part of which is defined by the sleeve inner surface, part of which isdefined by inner surfaces of the female die portions, and part of whichis defined by surfaces of the male die portions.

[0031] In preference the method of manufacture includes making the outermember by moulding or machining operations.

[0032] In preference in the method of manufacture the moulding cavity isso shaped that the length of the inner member not adjacent said sleeveflange is longer to allow for shrinkage of the inner member duringcooling.

[0033] In a still further form of the invention there is proposed a diefor moulding of the tail of a nut and tail assembly having a sleeve,said die including two separable complementary female die portionshaving inner surfaces defining a recess, and at least one male dieportion characterised in that the die moulding cavity is defined partlyby the outer surface of the annular flange of said sleeve when insertedinto said recess, partly by the recess surfaces of the female diemembers, partly by the inner surface of said sleeve, and partly by asurface of the male die portion.

[0034] In a yet further form of the invention there is proposed a fluidconnector including:

[0035] a longitudinal hollow body having a first connection means at oneend thereof, an outward flange at the other end thereof, and a stoplocated in between said ends;

[0036] a cylindrical sleeve located on top of said body between saidoutward flange and said stop

[0037] the diameter of said outward flange and said stop being greaterthan the diameter of the body between the two;

[0038] a nut having a second connection means at one end and a radiallyextending inward flange at the other end, said inward flange locatedbetween and of a smaller diameter than said body stop and outwardflange.

[0039] In preference said nut inward flange diameter is only slightlylarger than the diameter of the sleeve enabling said nut to slide alongsaid sleeve.

[0040] In preference said first connection means are external threadsand said second connection means are internal threads.

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated in andconstitute a part of this specification, illustrate severalimplementations of the invention and, together with the description,serve to explain the advantages and principles of the invention. In thedrawings,

[0042]FIG. 1 is a perspective view of a moulded fitting embodying thepresent invention and including a nut, tail, and sleeve;

[0043]FIG. 2 is a perspective view of the sleeve of FIG. 1;

[0044]FIG. 3 is a cross-sectional view of the moulded fitting of FIG. 1embodying the present invention;

[0045]FIG. 4 is a longitudinal cross-sectional view illustrating the dieused in the manufacture of the fitting or conduit;

[0046]FIG. 5 is a cross-sectional view of a moulded fitting having analternate configuration of a sleeve, according to the present invention;

[0047]FIG. 6 is a perspective view of a sleeve having yet a furtheralternate configuration and including integrally formed locatingprojections;

[0048]FIG. 7 (a) is a partial cross-sectional view of the sleeve, nut,and tail of FIG. 5 before the moulded plastic has cooled; and

[0049] (b) is a partial cross-sectional view as in FIG. 7(a) but whenthe moulded plastic has cooled causing shrinkage of the plastic.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0050] The following detailed description of the invention refers to theaccompanying drawings. Although the description includes exemplaryembodiments, other embodiments are possible, and changes may be made tothe embodiments described without departing from the spirit and scope ofthe invention. Wherever possible, the same reference numbers will beused throughout the drawings and the following description to refer tothe same and like parts.

[0051] Referring to the Figures there is shown a fitting 10 including anut 12, tail 14, and sleeve 16. Nut 12 includes a body 18 havinginternal threads 20, bore 22 at one end, and a radially inturned flange24 at the other end. The internal threads 20 are adapted to engageexternal threads of a suitable device such as a water meter or similardevice. An O-ring, washer, or gasket 26 is used within the nut 12 forsealing engagement with such device.

[0052] The outer surface of the nut 12 is of a non-circular shape 28 toenable a tool, such as a wrench, to be used to tighten the nut 12 uponapplication.

[0053] The tail 14 includes a longitudinal body 30 having externalthreads 32 at one end thereof, an outwardly extending integrally formedtorque converter 34 having a polygonal outer surface 36 assistingengagement of the converter 34 with an appropriate tool such as a wrench(not shown) that can be used to rotate the tail 14.

[0054] The tail 14 includes a stem 38 extending from the torqueconverter 34 longitudinally away from the external threads 32 and havingan outwardly extending radial flange 40. The flange 40 may include ashoulder (not shown) for retention of the gasket 26.

[0055] The sleeve 16 extends along the outer surface 42 of the tail 30between the torque converter 34 and the flange 40, the sleeve 16 at oneend including radially outward flange 44 that is correspondingly shapedto nestle in flange 40 of the tail stem 38. The other end of the sleeve16 extends into the tail body 30 under the torque converter 34.

[0056] The diameters of the stem 38, sleeve 16, and the nut flange 24are chosen so that the nut 12 can freely slide alongside the sleeve 16.That is, the inner diameter of the nut flange 24 is greater than theouter diameter of the sleeve 16. At the same time, the outer diameter ofthe outward flange 44 is greater than the inner diameter of the nutflange 40 so that the nut 12 remains captured and can slide alongsidethe stem 16 between the torque converter inner surface 46 and the innersurface 48 of the outward flange 44 of the sleeve 16.

[0057] In the method of manufacture of the nut and tail assembly 10,location pins 50 are used to hold the sleeve 16 in place before mouldingto thereby lock the sleeve 16 in position on the stem 38 with the sleeve16 partially extending into the tail 30. As illustrated in FIG. 1, fourpins 50 may be used, although it is to be understood that more or lessmay be used depending on the size of the sleeve and assembly. It is tobe understood that the pins 50 may be integral with the sleeve 16,although they are typically part of the die arrangement. If part of thedie arrangement, as the pins are removed, small apertures are left inthe flange 40 of the stem 38.

[0058]FIG. 4 illustrates a die 52 that is used in the method ofmanufacture of the nut and tail assembly 10 according to the presentinvention. The die 52 is provided with four parts, a front male portion54, a rear male portion 56 that upon die closure abuts the front maleportion 54, and two female portions 58 and 60 which, upon closure, abuteach other on an axial plane 62.

[0059] When the female portions 58 and 60 are closed they define acavity or recess 64.

[0060] In the manufacture of the assembly 10, however, sleeve 16 isfirstly inserted into nut 12 so that flanges 40 and 44 abut against eachother. The nut 12, with the sleeve 16 extending outwardly is thenpositioned in the front male portion 54 of the die 52 that includeslocating pins 50. The locating pins 50 are advantageous for a number ofreasons. Firstly, they ensure that the sleeve longitudinal axis isgenerally parallel to the axis 62. They also ensure that during themoulding operation the nut flange 24 abuts the sleeve flange 44 so thatthe determined thickness of the moulded plastic on the sleeve flange 44is achieved. Otherwise, if the sleeve 16 were to move axially towardsthe nut flange 24 during the moulding operation this thickness may bereduced leading to an unacceptable assembly where the sleeve 16 is notsupported within the tail 30.

[0061] When the female portions 58 and 60 are then closed they bearagainst the outer surfaces of the nut 12 and a portion of the sleeve 16establishing a moulding cavity 66. The moulding cavity 66 is thereforedefined by the surface or boundary of recess 64, partially by the frontand rear male portions 54 and 56 adjacent their mutual abutment zone,partially defined by the inner surface of the annular nut flange 24 andpartially defined by the sleeve 16.

[0062] The die 52 is typically formed from tool steel and is providedwith cooling conduits 68 therein. The die cavity, in which the tailforms flange 40, may have an additional shoulder recess (not shown) forretention of a sealing ring, typically an O-ring (not shown). In thecase of an O-ring, the tail may also include an overhang to capture theO-ring in position (not shown).

[0063] Fluent plastics material is injected into the die cavity 66.However the nut 12 is cold, and the die portions are rapidly cooled bythe cooling effect of the fluid flowing through the conduits 68. The dieportions are then separated, and the nut 12 and the sleeve 16 remaincaptive on the front end of the tail 14 due to the outstanding flangeportions 24 and 44 of the nut 12 and sleeve 16 and the outstandingflange portion 40 of the nut stem 38 that, by its moulding, is of acomplementary shape to the inner surface of the nut and sleeve flange 24and 44. The sleeve 16 is also captive since its other end, that is theend opposite to its flange, is now captured within the stem 38 of thetail 30.

[0064] It will now be readily apparent to the reader that the presentinvention ensures that there is provided a nut and tail assembly thathas a sleeve that improves upon the integral strength of the assembly.Further, the process of manufacture that includes the pins ensures thatthe assembly can be repeatedly made whilst ensuring quality standards.

[0065] The sleeve is typically made from metal such as brass that hasthe necessary strength to provide for support of the rest of thefitting.

[0066] In an alternate embodiment of the present invention and asillustrated in FIG. 5 is an assembly including sleeve 16, the sleeve atits outer end opposite to flange 44 including annular grooves 70. Thesegrooves 70 located at the end of the sleeve opposite the flange 44 areembedded within the stem 38 of the tail 14. During the mouldingoperation, the grooves 70 are filled with plastic that, when cools,integrally locks the sleeve 16 to the stem 38 thereby providingadditional support against longitudinal movement between the two. Ofcourse, instead of grooves the sleeve may very well have projectionsaround which forms the body during moulding.

[0067] In the embodiment discussed so far, locating pins 50 werepositioned on the die. However, not only do the locating features neednot be pins, but they may in fact be projections that are integrallyformed in the sleeve 16. Illustrated in FIG. 6 is such an arrangementwhere locating blocks projections or blocks 74 are part of the sleeve16. This may occur, for example, where one is using suitably strongplastic material, not necessarily metal, the sleeve 16 also being ableto be produced as part of a moulding operation.

[0068] One of the problems often encountered in moulding plastics isshrinkage. Where the plastic shrinks in one direction and does notencounter any resistance, only its size is reduced. However, theaddition of a sleeve results in the plastic encountering resistance whenshrinking in the longitudinal direction of the stem. For that reasons itis advantageous to construct a die so that when the plastic is stillhot, the inner diameter of the stem 74 projects further outwardly intothe nut 12 than the flange 40, as shown in FIG. 7(a). As the plasticcools, this portion 74 of the stem 38 retracts into the tail 30 whilstthe flange 40 of the tail 30 is prevented from retracting due to thesleeve flange 44. Since the amount of shrinkage can be pre-determinedmoulding a tail whose shape whilst hot is as in FIG. 7(a) can result inthe cooled shape being as illustrated in FIG. 7(b).

[0069] Those skilled in the art will now appreciate that the nut 12 canslidably move alongside the outer surface 42 of the sleeve 16. Thesleeve 16 is typically made from metal such as brass, thereby providingstrength to the assembly against any lateral forces.

[0070] It has been found that there is no tendency for adhesion orfusion to occur between the surfaces of the nut, sleeve, and tail, andupon shrinkage of the tail under cooling, the nut has been found to befreely rotatable about the tail. Since the surfaces are generallycircular, there is very good surface to surface contact as the nut istightened when in use.

[0071] It is to be understood that reference to flange throughout thedescription typically includes an annular flange.

[0072] The present invention provides of a nut and tail assembly thathaving a resilient sleeve, provides an assembly that withstands lateralforces whilst being manufacturable without expensive weld and inspectionoperations, at the same time reducing overall cost.

[0073] Further advantages and improvements may very well be made to thepresent invention without deviating from its scope. Although theinvention has been shown and described in what is conceived to be themost practical and preferred embodiment, it is recognized thatdepartures may be made therefrom within the scope and spirit of theinvention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices and apparatus.

1. A nut and tail assembly including: a longitudinal cylindrical hollowbody having a first end, said body including an outwardly extending stoplocated inwardly from said first end, said body further having anoutstanding flange at the second end thereof, said stop and flangedefining therein between a cavity sliding surface generally parallel tothe longitudinal body; a circular longitudinal sleeve extending alongsaid sliding surface; a nut having a first end, and an inward flange atthe other end, said nut inward flange extending into said body cavityand being of a diameter to be able to slide on said body slidingsurface.
 2. A nut and tail assembly including: a longitudinalcylindrical hollow body having a first end, said body including anoutwardly extending stop located inwardly from said first end, said bodyfurther having an outstanding flange at the second end thereof, saidstop and flange defining therein between a cavity sliding surfacegenerally parallel to the longitudinal body; a circular longitudinalsleeve extending along said sliding surface and having a flange at afirst end thereof, said flange abutting against said body flange; a nuthaving a first end, and an inward flange at the other end, said nutinward flange extending into said body cavity and being of a diameter tobe able to slide on said body sliding surface.
 3. A nut and tailassembly as in claim 1 wherein said body first end includes a pluralityof external threads.
 4. A nut and tail assembly as in claim 1 whereinsaid nut includes a plurality of internal threads at said first end. 5.A nut and tail assembly as in claim 2 wherein said sleeve other endextends into said body.
 6. A nut and tail assembly as in claim 2 whereinsaid sleeve other end includes at least one groove wherein said grooveassist in longitudinally anchoring said sleeve in said body.
 7. A nutand tail assembly as in claim 2 wherein said body is manufactured frompolymeric plastic.
 8. A nut and tail assembly as in claim 1 wherein saidsleeve is manufactured from metal.
 9. A nut and tail assembly as inclaim 2 wherein said sleeve includes projections extendinglongitudinally outwardly from said flange.
 10. A nut and tail assemblyas in claim 9 wherein said projections are located symmetrically andcircumferentially on said flange.
 11. A nut and tail assembly as inclaim 10 wherein there are at least four said projections.
 12. A nut andtail assembly as in claim 3 wherein located in between said sleeve andsaid external threads is a torque converter to assist in controlling therotational motion of the body including said tail and sleeve.
 13. A nutand tail assembly as in claim 2 including a gasket housed within saidnut and abutting against said body outstanding flange.
 14. A method ofmanufacture of a fitting with an inner member having a sleeve and anouter member that is rotatable over said sleeve, the method includingthe steps of: (a) making the outer member to a shape that includes aradially inturned annular flange at one end and an axially extendingportion having an internal thread, (b) placing a sleeve within saidouter member, said sleeve having a radial outwardly extending annularflange, said sleeve flange abutting against said outer member flange andextending longitudinally away from said internal thread, (c) positioningthe outer member and sleeve onto an axially aligned male portion of amoulding die and within two female portions said male portion includinga plurality of locating pins engaging said sleeve, (d) closing themoulding die thereby placing the outer member and sleeve in their finalposition and establishing a moulding cavity within which is located theouter member and sleeve, part of the surface of said cavity defined bythe outer surface of the sleeve annular flange, part of which is definedby the sleeve inner surface, part of which is defined by inner surfacesof the female die portions, and part of which is defined by surfaces ofthe male die portions.
 15. A method of manufacture of a fitting as inclaim 14 wherein making the outer member may include moulding ormachining operations.
 16. A method of manufacture of a fitting as inclaim 14 wherein the moulding cavity is so shaped that the length of theinner member not adjacent said sleeve flange is longer to allow forshrinkage of the inner member during cooling.
 17. A die for moulding ofthe tail of a nut and tail assembly having a sleeve, said die includingtwo separable complementary female die portions having inner surfacesdefining a recess, and at least one male die portion characterised inthat the die moulding cavity is defined partly by the outer surface ofthe annular flange of said sleeve when inserted into said recess, partlyby the recess surfaces of the female die members, partly by the innersurface of said sleeve, and partly by a surface of the male die portion.18. A fluid connector including: a longitudinal hollow body having afirst connection means at one end thereof, an outward flange at theother end thereof, and a stop located in between said ends; acylindrical sleeve located on top of said body between said outwardflange and said stop the diameter of said outward flange and said stopbeing greater than the diameter of the body between the two; a nuthaving a second connection means at one end and a radially extendinginward flange at the other end, said inward flange located between andof a smaller diameter than said body stop and outward flange.
 19. Afluid connector as in claim 18 wherein said nut inward flange diameteris only slightly larger than the diameter of the sleeve enabling saidnut to slide along said sleeve.
 20. A fluid connector as in claim 18wherein said first connection means are external threads and said secondconnection means are internal threads.